The presence and transfer characteristics of aflatoxins in medicinal herbs: From raw materials to edible dispensing granules

In this study, a sensitive and accurate immunoaffinity columns coupled with high-performance liquid chromatography method was established to monitor the presence of aflatoxins-aflatoxin B1 , aflatoxin B2 , aflatoxin G1 , and aflatoxin G2 -in different medicinal herbs. The proposed method was found to be suitable for the detection of aflatoxins in eight kinds of herbs and their corresponding granules. Two batches of Arecae semen were positive for aflatoxins, with high residue levels of different aflatoxins. To better understand the presence and transfer of aflatoxins during the formulation of dispensing granules from the herbs, the aflatoxins-free herbs were artificially inoculated with Aspergillus flavus to explore aflatoxins production. Both aflatoxin B1 and aflatoxin B2 were detected in all inoculated samples, while aflatoxin G2 was only detected in Astragali radix samples. Additionally, the presence of aflatoxin B1 was extremely high compared to other aflatoxins. More specifically, the transfer rate of the aflatoxin B1 and the total aflatoxins from original herbs to granules were both approximately 40%. These findings indicated that the preparation of herbs into dispensing granules reduced the content of aflatoxins. The high-level presence of aflatoxins in inoculated herbs indicated that attention is needed to the safety of A. flavus-contaminated herbs.